I have the Gigabyte GA-8KNXP and am booting from RAID-0 36gb Raptors with no problems, fast stable board too with lots of features, see
HERE . I am using both SATA controllers and recommend dumping the silicon image driver that comes on the mobo CD and installing the WHQL one from Silicons site, I was getting IRQL_LESS_THAN etc errors and reboots with the non WHQL driver
Andy